Any holes in your envelope will cause HVAC systems to work harder to maintain temperatures, which makes the entire home less efficient and more expensive.
AND, if there's a hole, air infiltration from the outside occurs bringing in dust, allergens, and other airborne pollutants.
Plus, air currents account for 98% of all water vapor movement in a building. Controlling the air means preventing unwanted moisture coming in from the outside.
How much moisture, for example, is transferred through a 1-inch hole exactly? 30 FULL QUARTS over a month.
And too many holes means you won't pass your door blower test. That's why you need an "air shield", or an Aeroseal.